Effect of mild sepsis on behavioral and biochemical changes on the stress-induced animal model of depression

Abstract

The systemic inflammation that occurs during severe sepsis can be the cause of long-term consequences. Studies have demonstrated a possible correlation between the neuroinflammatory process and depression. However, the effects of mild sepsis as a tolerant factor for some depressive parameters have not been described. Thus, the objective of this study is to evaluate the effect of mild sepsis on behavioral and biochemical changes on the stress-induced animal model of depression. To this aim, adult male Wistar rats were submitted to cecal ligation and perforation and after 30 days it was submitted to the chronic mild stress protocol (CMS). The animals were submitted to stressors for 40 days. To evaluate the efficacy of CMS induction anhedonia was determined as the amount of sweet food consumption. The levels of neurotrophins and oxidative damage were also evaluated in the hippocampus. It is observed that mild sepsis improved depressive-like parameters after CMS protocol associated with an increase of neurotrophins levels and a decrease of oxidative damage in the hippocampus. In conclusion, our data suggest that a previous mild systemic inflammation caused by the induction of mild sepsis could decrease consequences in the central nervous system (CNS) induced by CMS protocol.